Search Results
Results 351 - 400 of 1207
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Marques Sara - - 2004
Correct establishment of the left/right (L/R) body asymmetry in the mouse embryo requires asymmetric activation of the evolutionarily conserved Nodal signaling cascade in the left lateral plate mesoderm (L-LPM). Furthermore, the presence of Nodal in the node is essential for its own expression in the L-LPM. Here, we have characterized ...
Lavery S - - 2004
Preimplantation genetic diagnosis for haemophilia offers couples at risk for transmitting the condition the opportunity to embark on a pregnancy knowing that the embryo is unaffected by the disease. The technique aims to increase the range of reproductive options available to these couples and remove the need for invasive prenatal ...
Andrews Glen K - - 2004
The SLC30 family of cation diffusion transporters includes at least nine members in mammals, most of which have been documented to play a role in zinc transport. The founding member of this family, Znt1, was discovered by virtue of its ability to efflux zinc from cells and to protect them ...
Wang Haibin - - 2004
Ectopic pregnancy is a major reproductive health issue. Although other underlying causes remain largely unknown, one cause of ectopic pregnancy is embryo retention in the fallopian tube. Here we show that genetic or pharmacologic silencing of cannabinoid receptor CB1 causes retention of a large number of embryos in the mouse ...
Bass L D - - 2004
Equine embryos (n=43) were recovered nonsurgically 7-8 days after ovulation and randomly assigned to be cryopreserved in one of two cryoprotectants: 48% (15M) methanol (n=22) or 10% (136 M) glycerol (n=21). Embryos (300-1000 microm) were measured at five intervals after exposure to glycerol (0, 2, 5, 10 and 15 min) ...
McPherson John Peter - - 2004
The Drosophila melanogaster warts/lats tumour suppressor has two mammalian counterparts LATS1/Warts-1 and LATS2/Kpm. Here, we show that mammalian Lats orthologues exhibit distinct expression profiles according to germ cell layer origin. Lats2(-/-) embryos show overgrowth in restricted tissues of mesodermal lineage; however, lethality ultimately ensues on or before embryonic day 12.5 ...
Andacht Tracy - - 2004
The chick stage X blastoderm is routinely accessed through a small window in a freshly laid egg. However, windowing severely compromises embryo survival with hatch rates as low as a few percent. We previously reported a simple modification to the standard method that reduced introduction of air into the sealed ...
Spiegelstein Ofer - - 2004
Inactivation of folate binding protein-1 (Folbp1) adversely impacts murine embryonic development, as nullizygous embryos (Folbp1(-/-)) die in utero. Administration of folinic acid (N5-formyl-tetrahydrofolate) to Folbp1-deficient dams before and throughout gestation rescues the majority of embryos from premature death; however, a portion of surviving embryos develop structural malformations, including neural tube ...
Woodward B J - - 2004
Surrogacy and embryo donation remain beneficial but controversial infertility therapies. This is the first report of a pregnancy and subsequent birth of healthy twins following a surrogacy involving a female patient's biological mother as surrogate, but using anonymously donated embryos. Due to the novelty of combining intergenerational surrogacy with embryo ...
Lahijani Maryam Shams - - 2004
The effects of applying extremely low-frequency (50 Hz) electromagnetic fields (ELF-EMF) for 24 hr and different densities (1.33-7.32 mT) were examined on healthy, freshly fertilized white leghorn chicken eggs (55-65 g). Results showed no increase in the rate of abnormalities in exposed groups, but were only significant in 4.19, 5.32 ...
Ferguson, Clarence Edward
There has been great controversy involving progesterone (P<sub>4</sub>) levels during early pregnancy in cattle. The objectives of these experiments were to determine the effect of an early low dose administration of P<sub>4</sub> or altrenogest (ALT) on pregnancy rates in repeat breeder (RPB) females, if an increase in pregnancy rates could ...
Biggers J D - - 2004
The advice that should be given to a couple considering assisted reproductive technologies for the treatment of their infertility, when they are completely opposed to the destruction of surplus embryos, is discussed. It is urged that they do not use treatments that generate surplus embryos. They should be given the ...
Gabrielsen A - - 2004
BACKGROUND: Focus on the hatching process has so far been in the field of fresh embryos. Cryopreserved-thawed embryos have a lower rate of pregnancy than fresh embryos, which might be due to hardening of the zona pellucida. METHODS: During a 2 year period, a prospective randomized study enrolling 253 cryopreserved-thawed ...
Vyas S - - 2004
Superovulation, embryo recovery and transfer were attempted in 19 dromedary camels of about 6-10 years of age, and having calved at least once. Superovulation was done using two commercially available porcine FSH preparations, FSH-I (II donors) and FSH-2 (8 donors) during a luteal phase created by inducing ovulation with hCG. ...
Espinosa-Márquez M C - - 2004
The objective of this study was to evaluate if treatment of eCG-superovulated goats with fluorogestone acetate (FGA) would increase the number and quality of embryos recovered. Goats (n = 25) were given an intravaginal sponge containing 45 mg FGA for 12 days, with 1000 IU eCG and 7.5mg of Luprostiol ...
Rhind S M - - 2004
Maternal undernutrition and, under certain circumstances overnutrition, before or during pregnancy or during early postnatal life can alter reproductive function of the offspring. Effects can be exerted at many stages of development, from prior to conception until after birth and may be expressed at the time of the nutritional insult ...
Tao Jun - - 2004
OBJECTIVE: To evaluate the survival rate of human morula embryo freezing and the morphological alterations during freezing, during and after thawing, and their applications in embryo selection. DESIGN: Retrospective observational study. SETTING: Private infertility clinic. PATIENT(S): Consecutive patients under age 39 undergoing frozen morula embryo transfers from December 1999 to ...
Marrs Richard P - - 2004
OBJECTIVE: This study was undertaken to determine whether the method of fertilization has a significant impact on survival and/or clinical pregnancy rates of cryopreserved human pronuclear (2PN) stage embryos. DESIGN: A retrospective analysis of cryosurvival and clinical pregnancy rates after thawing of 2PN stage embryos from January 2000 through December ...
Young Todd E - - 2004
Maize is a monoecious species that produces imperfect (unisexual), highly derived flowers called florets. Within the spikelet, the basic repeating unit of the maize inflorescence, the spikelet meristem gives rise to an upper and a lower floret. Although initially bisexual, floret unisexuality is established through selective organ elimination. In addition, ...
Cameron R D A - - 2004
The objective was to determine farrowing rates and litter sizes that could be achieved in a typical farm-to-farm porcine embryo transfer program using vitrified blastocysts that were zona pellucida intact when cryopreserved. The embryos were transferred surgically on-farm into recipient sows that were managed throughout gestation and farrowing under the ...
Reina Michela - - 2004
PROBLEM: The immunological success of pregnancy is thought to depend upon the establishment of a balance between favorable and deleterious cytokines, the current paradigm viewing pregnancy as a T helper (Th)2 cytokine-dependent phenomenon. In this context, a particular attention should be directed to the potential role of interleukin (IL)-12, which ...
Nath Anjali K - - 2004
Nitric oxide (NO) has been demonstrated to mediate events during ovulation, pregnancy, blastocyst invasion and preimplantation embryogenesis. However, less is known about the role of NO during postimplantation development. Therefore, in this study, we explored the effects of NO during vascular development of the murine yolk sac, which begins shortly ...
Chang Chih-Yang - - 2004
OBJECTIVE: To test the safety and efficacy of a modified laser-assisted zonal opening method for human embryo biopsy. STUDY DESIGN: The embryo was treated with a modified method to create an ample perivitelline space between the zona pellucida and underlying blastomeres. This was done to protect the blastomeres from damage ...
Nitzan Yuval B - - 2004
Zinc is an essential element in mammalian development. However, little is known about concentrations of zinc in specific regions/organs in the embryo. We have employed selenite autometallography (AMG) and TSQ histofluoroscence to detect histochemically reactive (chelatable) zinc in whole midsagittal embryos and sections from neonatal mice. Chelatable zinc exhibited a ...
Mocé M L - - 2004
The aim of this work was to study the effects of the genotype of the dam, the embryo, or their interactions on prenatal growth by performing double-reciprocal embryo transfers between two lines of rabbits divergently selected for uterine capacity. Females from high (n = 53) and low (n = 48) ...
Breukelman S P - - 2004
The Large Offspring Syndrome has frequently been reported for in vitro produced calves. The objective of this study was to determine whether any differences in body dimensions (biparietal diameter of the cranium (BPD), cross-section of the abdomen at the insertion of the umbilical cord (CAU)) and heart rate (FHR) can ...
Wusteman Monica - - 2004
If large pieces of tissue and organs are to be successfully stored at low temperatures, some means must be found to minimize the disruption of extracellular structures by the ice that develops during conventional cryopreservation methods. The use of sufficiently high concentrations of cryoprotectant (CPA) to vitrify rather than freeze ...
Bényei B - - 2004
Holstein-Friesian dams (n = 28) and daughters (n = 28) were superovulated (total number of observations was 235) to determine the repeatability and heritability of ovulation number and embryo collection result for FSH treatment. The donor cows were superovulated with FSHp, artificial insemination was performed and embryo collection was carried ...
Crofts F - - 2004
BACKGROUND: Integrins such as VLA-4 (Very late antigen 4, integrin alpha4beta1) play key roles in cell-cell interactions that are critical for development. Homozygous null knockouts of the VLA-4 alpha4-subunit or VCAM-1 (VLA-4 cell surface ligand) in mice result in failure of the allantois and chorion to fuse leading to interrupted ...
Pelletier Cory - - 2004
OBJECTIVE: To characterize the architecture of the zona pellucida in living human eggs and embryos, noninvasively with the PolScope, a digital polarizing light microscope. DESIGN: The PolScope was used to examine zonae pellucida of living human eggs and embryos. SETTING: Academic IVF clinic. PATIENT(S): Patients undergoing fresh, nondonor infertility treatment ...
Andruss Bernard F - - 2004
Calmodulin (CaM) is an essential component of calcium signaling in multicellular organisms. We used null mutations of the Drosophila CaM gene (Cam) in combination with clonal analysis and immunolocalization to examine the effects of loss of Cam function in the ovarian germline and developing embryo. These studies have uncovered unexpected ...
Kattera Suresh - - 2004
BACKGROUND: Pronuclear zygote morphology has gained much attention recently due to its possible value in predicting implantation and pregnancy. The present study was performed to assess the developmental potential of zygotes with four different pronuclear orientations. METHODS: This prospective study involved 150 IVF and 190 ICSI patients seeking fertility treatment. ...
Revel A - - 2004
It is uncertain how long IVF units can keep frozen embryos. Few data exist on success of embryo transfer for embryos that have been cryopreserved for many years. We report the delivery of healthy twins following the transfer of embryos cryopreserved for 12 years. To the best of our knowledge, ...
Wharf Eleanor - - 2004
To maximize the chances of pregnancy during assisted reproduction treatment, it is important to be able to identify embryos with high implantation potential. Embryos which divide more quickly following insemination have been shown to produce higher pregnancy and implantation rates than those which divide later. The aim of this study ...
Leandro Nadja Suzana Mogyca - - 2004
This study evaluated the expression of heat shock protein 70 kD (hsp70) in broiler chicken embryos subjected to cold (Experiment I) or high incubation temperature (Experiment II). In each experiment, fertile eggs were distributed in three incubators kept at 37.8 degrees C. At day 13 (D13), D16, and D19 of ...
Godbole Savita - - 2004
In monocots, the zygotic embryo is protected and nourished by an endosperm. In the present study starch deposition and amylase accumulation was noticed during somatic embryogenesis in stem callus of a bamboo, Dendrocalamus hamiltonii. SEM studies revealed that starch grains were clearly visible in the scutellum during the maturation stage ...
Quadro Loredana - - 2004
Retinoids are required for normal embryonic development. Both embryonic retinoid deficiency and excess result in congenital malformations. There is little understanding of the physiology underlying retinoid transfer from the maternal circulation to the embryo. We now report studies that explore this process using retinol-binding protein-deficient (RBP-/-) mice and mice that ...
Weintraub Andrea S - - 2004
Appropriate temporal and spatial expression of osteopontin (OPN) in the female genital tract may be critical for successful embryo implantation and maintenance of gestation. Traditionally, experimental assessments of reproductive success have been limited to ex vivo dissection at a single time point to determine embryo number and size and are ...
Mocé M L - - 2004
The aim of this work was to determine whether prenatal survival depends on the genotype of the mother or of the embryo and to identify the critical periods for prenatal mortality in two lines of rabbits divergently selected by high (H) and low (L) uterine capacity. Does from H (n ...
Anitole-Misleh Katherine G - - 2004
Results of a number of pharmacological studies suggest that catecholamines play a regulatory role in cleavage, morphogenesis and cell differentiation during early animal embryonic development. Few studies, however, have actually assayed for levels of catecholamines in these early embryos by methods that are both sensitive and specific. In this investigation ...
Hansen Peter J - - 2004
Structural features of the dairy industry make it well situated to use embryo technologies as tools for enhancing the genetic merit of dairy cattle and improving fertility. Technologies dependent upon embryo transfer have the potential to increase the efficiency of quantitative genetic selection as well as marker-assisted selection, simplify cross-breeding ...
Fischer-Brown A E - - 2004
Bovine embryos were produced in vitro using a 2 x 2 design of modified medium (KSOM or SOF) and oxygen concentration (5% or 20%). Day 7 blastocysts were transferred in bulk (n = 11, on average) to recipient heifers and recovered non-surgically at Day 14. In two replications of a ...
Acton B M - - 2004
Mitochondria are cellular organelles regulating metabolism and cell death pathways. This study examined changes in mitochondrial membrane potential (deltapsim) throughout the stages of preimplantation development in mouse embryos conceived either in vivo or in vitro and human embryos donated to research from IVF. Embryos stained with the deltapsim-sensitive dye (JC-1) ...
Cheng Tzu-Chun - - 2004
Leukemia inhibitory factor (LIF) is an essential factor for implantation and establishment of pregnancy. However, its role in the development of preimplantation embryos remains controversial. In this study, changes in preimplantation embryos were determined after microinjection of LIF antisense oligonucleotide at the two-pronucleus stage. Although no significant differences were found ...
Hasler John F - - 2003
A commercially viable cattle embryo transfer (ET) industry was established in North America during the early 1970s, approximately 80 years after the first successful embryo transfer was reported in a mammal. Initially, techniques for recovering and transferring cattle embryos were exclusively surgical. However, by the late 1970s, most embryos were ...
Babiak Igor - - 2003
Prolonged access to early embryos composed of undifferentiated, totipotent blastomeres is desirable in situations when multiple collections of gametes are not possible. The objective of the present study is to examine whether the refrigeration of rainbow trout Oncorhynchus mykiss gametes and early embryos would be a suitable, reliable, and efficient ...
Sugimoto Michihiko - - 2003
tclw5 is a t-complex recessive lethal mutation of the tw5-haplotype. Since tw5/tw5 embryos die soon after implantation, the tclw5 gene is thought to play an important role in early embryogenesis. Previous histological studies have demonstrated that tw5 homozygotes do not survive past the gastrulation stage due to extensive death of ...
Spandorfer S D - - 2003
To examine the roles of Interleukin-1 (IL-1) and IL-1 receptor antagonist (IL-1ra), in in vitro embryo development and subsequent pregnancy outcome. Maternal serum utilized to supplement embryo growth in IVF cycles was analyzed for the presence of IL-1 cytokines. The maternal serum that was utilized to supplement the embryo media ...
Pribenszky Csaba - - 2003
The objective of the present study was to examine the effect of rapid freezing on the in vitro and in vivo survival of zona-pellucida-free hatched mouse blastocysts. Hatched blastocysts were rapidly frozen in a freezing medium containing either ethylene glycol (EG) or glycerol (G) in 1.5 M or 3 M ...
Wong Benjamin C - - 2003
OBJECTIVE: To assess the effect of laser hatching on human embryo damage and subsequent development using the Zona Infrared Laser Optical System (ZILOS). DESIGN: Randomized controlled study. SETTING: Tertiary care fertility clinic. PATIENT(S): One hundred fourteen donated and discarded frozen human embryos. INTERVENTION(S): Embryos were thawed, cultured with cleavage and ...
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